package model;

//import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;

import com.mysql.cj.jdbc.MysqlDataSource;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * 和数据库建立连接
 */
public class DBUtil {
    private static final String URL="jdbc:mysql://127.0.0.1:3306/lt_myweb?characterEncoding=utf8&useSSL=true&serverTimezone=UTC&useTimezone=true&" +
            "serverTimezone=GMT%2B8&allowPublicKeyRetrieval=true";
    private static final String USERNAME="root";
    private static final String PASSWORD="root";

    private static volatile DataSource dataSource=null;

    private static DataSource getDataSource(){
        if (dataSource==null){
            synchronized (DBUtil.class){
                if (dataSource==null) {
                    dataSource = new MysqlDataSource();
                    ((MysqlDataSource) dataSource).setURL(URL);
                    ((MysqlDataSource) dataSource).setUser(USERNAME);
                    ((MysqlDataSource) dataSource).setPassword(PASSWORD);
                }
            }
        }
        return dataSource;
    }

    public static Connection getConnection() throws SQLException {
        return getDataSource().getConnection();
    }

    public static void close(Connection connection, PreparedStatement preparedStatement, ResultSet resultSet){
        if (connection!=null){
            try {
                connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (preparedStatement!=null){
            try {
                preparedStatement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (resultSet!=null){
            try {
                resultSet.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

}
